Merle M. Millard

Continuous Low-Temperature Discharge Treatment of Wool Yarn A Process for Making Wool Yarn Oil Repellent and Shrink Resistant

A continuous discharge process has been developed to make wool yarn shrink resistant and oil repellent. A commer cially available fluorocarbon monomer was adsorbed on wool yarn and permanently grafted to the yarn by exposure to a low temperature discharge. Yarn was obtained with less than one percent fluorocarbon add-on after extensive extrac tion with a solvent in which the monomer and homopolymer are soluble. Yarn with high levels of oil repellency and fabrics with area shrinkage between 5% and 10% was obtained. The effect of process variables such as discharge power and concentration of adsorbed fluorocarbon were studied. X-ray photoetectron spectroscopy was used to detect the fluorocarbon graft on the yarn and to estimate the change in the concentration of the fluorocarbon graft on the yarn after solvent extraction and laundry tests.

Surface Analysis of Wool Fibers and Fiber Coatings by X-Ray Photoelectron Spectroscopy

X-ray photoelectron spectroscopy was used to detect coatings and chemical changes on the surface of wool fibers. Organic coatings containing fluorine, phosphorus, and silicon were detected on the surface of fibers by measuring the binding energy of core electrons ejected from the surface by x-rays. Changes in the concentration of these coatings on the surface of fibers were estimated from the area under the core electron binding-energy curve. Changes taking place on the surface of wool fibers subjected to oxidation in an electrical discharge were studied. Sulfur atoms on the surface , of the fiber were found to be oxidized to the plus six oxidation state by these treatments. The general application of x-ray photoelectron spectroscopy for the surface analysis of coatings and fibers is discussed.

Surface analysis and depth profile composition of bacterial cells by x-ray photoelectron spectroscopy and oxygen plasma etching.

Summary X-ray photoelectron spectroscopy (XPS) was used to analyze the outermost (2–5 nm) surface of bacterial cells. Elemental analysis of the cell surfaces in Bacillus subtilis 168 and Bacillus megaterium KM gave a strong P signal attributed to teichoic acids. Teichoic acid-less Microccus lysodeikticus ha a very weak P signal. Oxygen plasma etching (OPE) combined with XPS and electron microscopy was used to obtain depth profiles of the cell surfaces. Distribution of P (teichoic acid) throughout the cell wall of the two Bacillus species was demonstrated. Separated of the two membranes in Escherichia coli B by their P signal was however not achieved. Na, the common surface cation, was replaced by K upon surface etching. Atomic ratios (C:O:N) of the surface biopolymers essentially agreed with known surface composition.

Analysis of X-ray Photoelectron Spectra Through Their Even Derivatives

The analysis of organic and inorganic surfaces can be carried out very effectively with the aid of x-ray photoelectron spectroscopy. In many cases, however, the presently available methods and techniques for data treatment resolutions are not suitable for the qualitative and quantitative identification of the various forms of a given atom on the same surface. The number of components and a good approximation of their original position in the composite curve must be known to use the available curve fitting procedures, otherwise the evaluation can be unreliable. It is suggested that the second and higher even derivatives of the composite could provide these data. The possibility of applying even derivatives of composite curves in combination with a nonlinear least square curve fitting program was investigated. It was found that depending on the noise background of the spectra, the resolution could be improved through this method. The resolution is dependent on the half-width of the component curves, their separation, and ratio. Both Gaussian and Lorentzian curves can be resolved, but the resolution of the latter is easier. The resolution is increasing with higher derivatives; however, increased smoothing must be applied at each step to neutralize the influence of the noise background.

Surface Analysis of Plasma Treated Wool Fibers by X-Ray Photoelectron Spectroscopy

Chemical changes on the surface of wool fiber as a result of low temperature plasma treatment were analyzed using X-ray photoelectron spectroscopy. Extensive changes in the electron spectra of carbon, nitrogen, and oxygen were observed. The carbon is electron spectra were deconvoluted into three electron lines. Two lines at higher binding energies resulted from surface oxidation. Two nitrogen and two oxygen is lines were present before and after plasma treatment. However, the intensity of these two lines changed considerably with treatment. The surface atom concentration before and after treatment was calculated from electron line intensities. The principal result of plasma treatment was found to be extensive surface oxidation of the wool fibers.

MAGNETIC RESONANCE IMAGING OF TISSUE-SPECIFIC THERMAL RESPONSES OF GERANIUM STEM IN VIVO

Abstract 1. 1. Tissue-specific variations in the responses of geranium stems to hyperthermia were investigated in vivo by acquiring tissue water proton spin-spin (T 2 ) relaxation images at different sample temperatures and calculating the apparent activation energy (E a ) and entropy (ΔS ‡ ) for each image voxel [(39 μm × 39 μm) × 500 μm]. 2. 2. After partitioning the images by tissue type, Eyring analyses of the temperature dependence of water proton T 2 relaxation demonstrated increases in E a or ΔH ‡ when the sample temperature exceeded 26.5, 45.7, 32.4 and 31.1°C for the pith parenchyma, fibrous sheath/vascular tissues, cortical parenchyma/epidermal tissues and whole stem, respectively. 3. 3. The results suggest that the changes in T 2 thermodynamics are caused primarily by direct temperature-dependent variations in the physical state of tissue water, while a standard viability assay measures thermally-induced protein denaturation. 4. 4. This is apparently the first in vivo demonstration of tissue-specific variations in a plant response to hyperthermia.